Blow molded plastic container with inclined mouth and method and apparatus for obtaining same

ABSTRACT

Method and apparatus for blow molding a plastic container with a mouth and neck portion thereof which is inclined or angled with respect to the body portion of the container, plus a plastic container having an inclined or angled mouth and neck portion.

BACKGROUND OF THE INVENTION

The present invention relates to a blow molded, plastic container havingan inclined or angled mouth and neck portion, and a method and apparatusfor preparing same.

Blow molded plastic containers, such as those made from polyethyleneterephthalate, are widely used for many applications, such as, forexample, as containers for drinks and cleaning products. Thesecontainers customarily have a straight mouth and neck portion, that is,a mouth and neck portion that are coaxial with the body portion of thecontainer.

The preparation of these containers generally involves preparing apreform or parison with a mouth and neck portion that are coaxial withthe preform body portion, holding the preform in a blow mold with thepreform mouth and neck portion held coaxial with the preform bodyportion, and forming the desired container in the shape of the blow moldby stretching and blow molding.

For many applications it is desirable to prepare such a container with amouth and neck portion at an angle to the body portion of the container.However, it is difficult to prepare such an angled mouth and neckportion container by conventional blow molding techniques. For example,such techniques may involve expensive and inconvenient multistageoperations where an injected preform is clamped, stretched and blown inthe mold at one station and a blow pin is inserted into the mold forblowing and/or compression molding at another station and the neck isbent at a subsequent station or in a subsequent stage of operation.Techniques such as this increase the cost of the container andcomplicate processing.

Alternatively, a conventional type apparatus cannot be satisfactorilyused to mold a container with an angled mouth and neck portion since todo so would require the mold cavity to be aligned so that the desiredangular neck is appropriately aligned with the blow pin. Significantprocessing problems result thereby, as well as problems with theresultant container.

Accordingly, it is a principal objective of the present invention toprovide a new and improved method and apparatus for obtaining a blowmolded, plastic container with an angled or inclined neck and mouthportion.

It is a still further objective of the present invention to provide animproved blow molded, plastic container with an angled or inclined neckand mouth portion.

It is an additional objective of the present invention to provide amethod and apparatus as aforesaid which is easy and expeditious to useon a commercial scale, and which simply and conveniently providesimproved containers as aforesaid.

Further objects and advantages of the present invention will appearhereinbelow.

SUMMARY OF THE INVENTION

In accordance with the present invention it has now been found that theforegoing objects and advantages are readily obtained.

The present invention provides a method of forming a blow molded plasticcontainer, preferably polyethylene terephthalate although other plasticmaterials can be readily used, said container having a mouth and neckportion thereof which are inclined or angled with respect to the bodyportion of the container. The method comprises:

providing a straight, cylindrical plastic parison or preform having aclosed base, straight body portion extending therefrom, straight neckportion extending from the body portion, and an open mouth;

placing said preform in a blow mold having the desired containerconfiguration and clamping or holding the preform in place in the blowmold;

introducing a stretch rod into the preform and extending said preformsubstantially to the base of the blow mold with said stretch rod toprovide an extended preform;

providing a blow nozzle with an angled face corresponding to the desiredangle of the mouth and neck portion of the container, generally lessthan 45° with respect to the longitudinal axis of the container;

engaging said angled face of the blow nozzle with the open mouth of thepreform and bending the open mouth and neck portion of the preform bythe angled face of the blow nozzle to correspond to the angle of theface of the blow nozzle; and

introducing high pressure air into the extended bent neck preform fromthe blow nozzle to stretch the extended bent neck preform intoconformity with the shape of the blow mold and to provide a biaxiallyoriented container having an angled mouth and neck portion.

The apparatus of the present invention comprises:

a blow mold having the desired container configuration for holding inplace therein a straight, cylindrical plastic parison or preform havinga closed base, straight body portion extending from the base, straightneck portion extending from the body portion, and open mouth;

a stretch rod associated with the blow mold for introduction to thepreform operative to extend the preform substantially to the base of theblow mold and provide an extended preform;

a blow nozzle associated with the blow mold having an angled facecorresponding to the desired angle of the mouth and neck portion of thecontainer, generally less than 45° with respect to the longitudinal axisof the container;

wherein said angled face of the blow nozzle is operative to engage theopen mouth of the preform and bend the open mouth and neck portion ofthe preform to correspond to the angle of the face of the blow nozzle,and wherein said blow nozzle is operative to introduce high pressure airinto the angled mouth and neck of the extended preform to stretch theextended preform into conformity with the shape of the blow mold and toprovide a biaxially oriented container having an angled mouth and neckportion.

The container of the present invention comprises:

a biaxially oriented, blow molded container prepared from a straight,cylindrical preform or parison, said container having a closed base, abody portion extending from the closed base, a neck portion extendingfrom the body portion, an open mouth, and a longitudinal axis; whereinsaid body portion has an upper portion and a lower portion, and in crosssection one side of the upper body portion includes a gradual,continuous, curved configuration extending to the angled neck, and theopposed side of the upper portion has a stepped configuration extendingto the angled neck.

The container of the present invention is desirably polyethyleneterephthalate and may if desired include an amount of post consumerresin (PCR), for example, up to about 75%. Also, if desired thecontainer may be of a multilayer construction. Desirably, the containermay have a threaded neck and an outwardly extending flange in the neckportion beneath the threaded portion.

Other features and advantages of the present invention will appearhereinbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more readily understandable from aconsideration of the following illustrative drawings, wherein:

FIG. 1 is a side view showing the preform positioned in the blow mold,with the stretch rod positioned in the preform and the blow nozzlepositioned above the blow mold;

FIG. 2 is a view similar to FIG. 1 in a further stage of operation withthe stretch rod extending the preform;

FIG. 3 is a view similar to FIG. 1 in a further stage of operation withthe blow nozzle coming into engagement with the preform;

FIG. 4 is a view similar to FIG. 1 in a further stage of operation withthe blow nozzle in full engagement with the preform and bending themouth and neck portion of the preform into the desired angle;

FIG. 5 is a view similar to FIG. 1 in a further stage of operationshowing the blow nozzle in full engagement with the bent neck and mouthpreform and with an anti-rotation arrangement to prevent rotation of theblow nozzle;

FIG. 6 is a view similar to FIG. 1 in a further stage of operationshowing the final blow molded container with stretch rod and blow nozzleretracted therefrom, and FIG. 6A is a modification of FIG. 6; and

FIG. 7 is a side view of the container of the present invention preparedin accordance with FIGS. 1-6, and FIGS. 7A & 7B are partial sectionalviews of the wall structure of the container.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the drawings, FIG. 1 shows a straight, cylindrical, plasticpreform or parison 10 having a closed base 12, a straight body portion14 extending therefrom, a straight neck portion 16 extending from thebody portion, and an open mouth 18. If desired, the preform has athreaded neck portion 20 and an outwardly extending flange 22, whichaids in seating the preform 10 in the blow mold 24. The blow mold 24 isclosed on the preform firmly seating the preform in the blow mold.

Stretch rod 26 is positioned within the preform and blow nozzle 28 isspaced above the preform. It is noted from FIG. 1 that blow nozzle 28has an angled face 30 which faces the preform, rather than theconventional flat face. Locking flange 32 is provided in the upperportion of the blow nozzle to lock the assembly in place.

FIG. 2 shows the stretch rod 26 fully extended in the clamped preform toextend the preform to the base 34 of the blow mold and to provide anextended preform 11, while FIG. 3 shows the angled face 30 of the blownozzle 28 moving into engagement with the mouth 18 of the preform,commencing the bending of the mouth 18 and neck 16 of the extendedpreform 11 into the desired angled orientation. In FIG. 3, the angledface 30 of the blow nozzle 28 just starts to make contact with the openmouth 18 of the extended preform. It is noted that blow mold 24 includesan angled upper portion 25 to engage the outwardly extended flange 22 ofthe preform at an angle which corresponds to the angle of the face ofthe blow nozzle and to insure a proper angled open mouth and neckportion. In FIG. 4, the blow nozzle 28 continues downwardly, bending theopen mouth 18 and neck portion 16 of the extended preform to an angularorientation which corresponds to the angle of the angled face 30 of theblow nozzle, i.e., less than 45° with respect to the longitudinal axisof the preform.

FIG. 5 shows anti-rotation element 36 to prevent rotation of blow nozzle28. High pressure air is then introduced into the extended preformthrough the blow nozzle from a high pressure air source (not shown) tostretch the extended preform into conformity with cavity 38 of blow mold24 and form container 40 shown in FIGS. 6-7.

FIG. 6A is a variation of FIG. 6 and shows the mold and/or mold cavityplaced at an angle of from 1 to 45° in relation to the stretch rod. Inaccordance with the variation of FIG. 6A, at least a portion of the moldcavity may conveniently be placed at said angle in relation to thestretch rod, and the preform appropriately processed at said angle.

As shown in FIG. 7, container 40 has a closed base 42, a body portion 44extending from the closed base, a neck portion 46 extending from thebody portion, and an open mouth 48. The neck portion and open mouth areat an angle of less than 45° with respect to the longitudinal axis 50 ofthe container 40. The container body portion 44 has an upper bodyportion 52 and a lower body portion 54. In cross-section, one side ofthe upper body portion includes a gradual, continuous curvedconfiguration 56 extending to the curved neck, while the opposed side ofthe upper portion has a stepped configuration 58 extending to the curvedneck. Container 40 also has a threaded neck 60 and outwardly extendingflanges 62. In addition, the container is biaxially oriented. Thecontainer can have a multi-layer wall structure as shown in FIG. 7A, ora single layer wall structure as shown in FIG. 7B.

After completion of the blow molding operation, the stretch rod followedby the blow nozzle is retracted from the newly formed container, theblow mold is opened, and the newly formed container is removed.

Preferably, the plastic is polyethylene terephthalate; however, othersuitable thermoplastic plastics may be readily used alone or incombination or in a multilayered configuration. For example,polyolefins, polyethylene naphthalate, polyvinyl chloride, and others.

It is to be understood that the invention is not limited to theillustrations described and shown herein, which are deemed to be merelyillustrative of the best modes of carrying out the invention, and whichare susceptible of modification of form, size, arrangement of parts anddetails of operation. The invention rather is intended to encompass allsuch modifications which are within its spirit and scope as defined bythe claims.

What is claimed is:
 1. Method of forming a blow molded, plasticcontainer with a mouth and neck portion thereof which is inclined orangled with respect to the body portion of the container, whichcomprises: providing a straight, cylindrical plastic preform having aclosed base, straight body portion extending therefrom, straight neckportion extending from the body portion, and open mouth; placing saidpreform in a blow mold having the desired container configuration andholding said preform in place in the blow mold; introducing a stretchrod into the preform and extending said preform substantially to thebase of the blow mold with said stretch rod to provide an extendedpreform; providing a blow nozzle with an angled face corresponding tothe desired angle of the mouth and neck portion of the container;engaging said angled face of the blow nozzle with the open mouth of thepreform and bending the open mouth and neck portion of the preform bythe angled face of the blow nozzle to correspond to the angle of theface of the blow nozzle; and introducing high pressure air into theextended bent neck preform from the blow nozzle to stretch the extendedbent neck preform into conformity with the shape of the blow mold and toprovide a biaxially oriented container having an angled mouth and neckportion.
 2. Method according to claim 1, wherein the angled face of theblow nozzle is less than 45°, and wherein said angled face bends theopen mouth and neck portion of the preform to a corresponding angle ofless than 45°.
 3. Method according to claim 1, including providing aplastic preform of polyethylene terephthalate.
 4. Method according toclaim 1, including providing a preform which contains post consumerresin.
 5. Method according to claim 1, including providing amulti-layered preform.
 6. Method according to claim 1, includingproviding a preform which includes a threaded neck portion and anoutwardly extending flange portion beneath the threaded neck portion. 7.Method according to claim 6, wherein said open mouth and neck portion ofthe preform is bent by the angled face of the blow nozzle so that theoutwardly extending flange of the preform engages an angled portion ofthe blow mold.
 8. Method according to claim 1, wherein the preform isplaced in a mold cavity of the blow mold, and wherein the mold cavity isplaced at an angle of from 1 to 45° with respect to the stretch rod.